Telegraph switching system



July 10, 1945. w ZENNER TELEGRAPH swucnme SYSTEM Filed March 3, 1945 3 Sheets-Sheet l INVENTOR WALTER J. ZENNER mi mm- ATT RNEY July 10, 1945. w. J. ZENNER 2,380,007

' TELEGRAPH SWITCHING SYSTEM Filed March 3, 1943 I5 Sheets-Sheet 2 p INVENTOR WALTER J. ZENNER J z z ma K63 AT RNEY 5 Sheets-Sheet 3 .nhr v 2 y 1945- w. J. ZENNER TELEGRAPH SWITCHING SYSTEM Filed Mal 01 3, 1943 INVENTOR BY WALTER J ZENNER ATT RNEY Patented July 10, 1945 TELEG APHswlrcnmofsys'rnM Walter J. Zenne nDes Plaines; "111;, assignor to Chicago, Ill., acorpora- "Teletype Corporation tion of Delaware "1 Application March; 3, 1943, Sam 15ft. 477,800:

' 6 Claims. (c1. '17s 2)u.

This invention "pertains to printing telegraph systems and particularly to apparatuszfor'automatically selecting central ofiice retransmission equipment under the control of relay station identification signals. 1 i

- In ajtelegraph system in" which outlying stations transmit intelligence to a central station where, there are located several tape reperforators for preparing retransmission tape, it is desirable under-some conditions of message relaying practice tobe able to choose, iromamong several outlying message broadcast stations certain ones only for particular channels of retransmission under circumstances whereby these channels will 0 respond to limited traffic only and whereby the selection from among several outlying broadcast stations is made under the supervision of identiiying signalswhich accompanying each message and which designate its particular originating station. g 3 H 0 Accordingly, the primary object of the-present invention is the provision of an automatic te1e graph switching system by means of which transmitting stations can cause to:be selected from among several transmitting. or broadcasting stations those, through which it is desired to relay themessage. t y a l In accordance with the, present inventionthere is provided,.at a central station, a selector mech anism which is associated with arelay unitand Y "which isoperated in accordance with preassigned identification signalslreceived from and indicative Which reperforators are selectedfdepends upon how a particular selecting relay isccnnected to the several reperforatorshunt relays ,as will ap-.

pear from the detailed description to follow. The" number of selecting relays used and the number of reperforators and associated transmitters employed is an arbitrary choice and the invention isnot. to be limited by such specific recitals.

t In practicingthe present invention flit has been found preferable to utilize nonprinting or socalled-function signalsv for station selecting purposes in order that confusion with messagefmatter might not result: Accordingly the station selection ,or control signals chosen for use in operatingthe present system are'the carriage re- ,turn, letters shift, space, blank, andlinefeed.

The invention will ,nowbemore completely described withreference to the accompanying drawings wherein;

I .Fig.-.1 isa schematic circuit diagram ofa systemembodying the present invention;

Eig..2is a portion of abomplete circuit diagram in which portion are shown the four rep'erforator shunt relays; I

Fig. 3 is another, portion of the complete circuit diagram in which the nine selecting relaysused in thesystem arefshown; and

, Fig. 4 is a portion of the circuit diagram illustrating symbolically certain elements of aselector and three circuitlconditioning relays.

Referring now particularly to Fig. 1, there is illustrated a schematic circuit diagram ofthe systern embodied the present invention A pluralit 'of outlyingjstations H, [2,13, etc., are shown connectedserially over a signal line 14 to 'a-master receiving relay l5, located at a central station 15., The operation of receiving relay l5 causesthe simultaneous operation of relays l1, [8,- IB, andv associated respectively with reperforators22, 23, 24, and and also the simultaneous. operation of relays 26 and-21 associated respectively with a contact operating selector Z8 anda monitor printer, 29 which makesa record of all incomingsignals. The circuit for this simultaneous operation is as follows: irompositive battery through'the" windings of relays l1, 18,19, 20, 26,1and 21, over conductor 3| and through transmitting tongue 32 ofthe master receiving relay [5 to negative battery.

" Also shown in the schematic circuit diagramof Fig. 1 is a relay unit 33 'which includes four reperforatonshunt,relays34, 35, 3B,'and 3'', respectivelylassociated with reperforators 22, 23, 24,

and25 Each ofthe relays 34 to 31 is provided ,witha shunting contact tongue 38 and a pair of shunting conductors 39 and 41 which normally provide a shunt j circuit to the 'reperforator .operating contact tongues 42 associated with therelays I! to 20. As ones of the reperforator shunt relays 34 to 31 are selected, their associated contact tongues 38 are attracted, openingthe shunt circuit to the contacts 42 and permitting the operation of said contacts 42 thereafter to efiectively control their related reperforators '22 to 25.

Associatedwith reperf orators 22, 23,24, and 25,

j are the respective tape transmitters 43, 44; 45,

and 46 which receive the tapeor'control form prepared by the reperforators and transmit cor- A E O F responding signals over the individual outgoing lines 41, 48, 49, and 5|, on each of which there may be any number of subscribers stations.

Referring now particularly to Figs. 2 and 4, the primary elements whose performance effects the selection of the reperforator shunt relays 34, 35,

36, and 31 will be described in detail. As has already been mentioned, there is located at the central station I6 a mechanical selector or contact closer 28 which exercises a selective control over a set of contact switching pull bars as de scribed in copending application Serial No 405,301 of W. J. Zenner filed August 4, i941, now- Patent No. 2,323,438, granted July 6, 1,953, The

'pull bar contacts include a letters shift contact pair 52, a space contact pair 53, and a blank contact pair 54. There is also included in the, selector apparatus a carriage return'contact pair tablished for energizing the conditioning relay 62: from positive potential, over conductors 66 and 68, through the winding of conditioning relay 62, over conductor63, through contact tongue H of conditioning relay 63, now unattracted due to an'dattracts its contact tongue 14 to prepare a 55 which has a circuit conditioning function, and,

a line feed contact pair 56 which performs a circuit breaking function and whose pull bar differs from the other pull bars'in that it breaks or opens its contact pair instead of closing it. Further, the selector '28 provides a universal bar. operated contact pair 51 and a platen shift contact pair 58 which is only closed when the platen is in its letters shift position. The letters shift, space, and blank code bar contact pairs operate to perform their switching functions only when the selector apparatus is in its letters shift position.

The outlying message broadcasting stations I I, i2, and I3 will transmit prior to each message, preassigned station identifying signal code combinations which will also serve to select predetermined reperforators for operation, as will now be described. The broadcast stations will beg n each message by first transmitting a carriage return signal followed by a combination of signals of the letters shift, space, and blank signals, and then a second carriage return signal.

The .a-fore-mentioned carriage return. signals control the operation of the circuit conditioning relays .6]. 62, and 63, Fig, 4.. The preceding of the message proper by a carriage return signal is particularly desirable inasmuch as it insures that monitoring printing equipment w ll always be in proper position .for printing thebeginning of a message.

In order to illustrate the invention, it'will be presumed that an outlying station H. is transmittingra message and that the outgoing signal lines 48 and 5| are to be the only ones of the repeaters which respond to message. Referring to Fig.3, there are disclosed nine selectin relays, one of which. is .se'lectedflfor operation according .to the identification signals transmitted by any of the stations, as explained above made up of the signal components, letters shift,. space, and blank. Let it be supposed that spaceblank is the identification signal used by station 1H so that accordingly relay 6'] is operated'as will appear. As already explained, the space-blank signal will be preceded and followed by the carriage return signals in order to set the conditioning relays .61, 62, and B3 The receipt of the first carriage return signal by the selector .28 causes its associated carriage return pull bar H8 to be selected for operation and to close the carriage return contact pair .55. since universal contact .5] is closed uponthe reception of ever-y signal combination and .the letters shift'platen controlled contact pair 58 is closed due to theselector apparatus being in its letters shift position, the following circuit is cslocking circuit for tl-ie conditioning relays 62 and 63-which isefiective upon the opening of the carriage return cont-act 55. This circuit is traceable a follows; from positive potential over conductors66 and, through the winding of relay 62, through contact tongue 14 (now attracted), over conductor 15, through the winding of conditionin relay 63,'over conductor '16, through line feed contact pa-ir 56"-(nor-mally closed) and over the conductor 13 to negative potential. When the carriage return contact pair 'opens, interruptnine selecting relays-shown in Fig. 3- as follows:

from negative potential conductor 13, through the platen shift contact pair 58, through the universal contact pairiil (when closed), over conductor'lil, through contact tongue 1-! of con- 'ditioning relay 6 2 (now attracted) over conductor .19 through contact tongue 8| of conditioning relay 6i (now de-e'ner'gized) over the conductor 82 to the letters shift, spacejand blank contact pairs. It is'thus apparent that when either the letters shift, space, or blank contacts are closed, negative potential may be extended over their respective conductors 83, 84, or 85, for the'operation of the selecting relays shown in Fig. 3.

As a result of the operation'of relay 63', tongue '86 pulls up and extends negative locking potential to the nine relays shown in Fig. 3, over conductor 88 as followszfrom negative conductor 13, through contact'tong'ue {86 (now attracted) over conductor 81 to conductor 88.

With conditioning relays 62 and 63 thus operated, the description of a typical selection will be continued durin whichthe outlying station H next transmits aspace signalv to cause the operation of space relay 89 shown in Fig. 3. The circuit for relay B3 is traceable from the negative common line 82 to which this potential was .de-

scribed above, the space contact 53 (now operated by its pull bar 118), over the space conductor 84,

' through contact tongue 9! of letters shift relay 92 (now de-energizedL" over conductor 93,

through contact tongue 94 of blank relay 95 (now de-energized), over conductor 96, through the winding of space relay 89 and over conductor 91 to positive conductor 65. Y

- winding 89through its armature 'I I! (now closed),

line 1116 to the intermediate oi. a make-beforebreak contact assembly of relay I 15, its normally closed contact H4, H3 to the intermediate contact of .a make-before-break contact assembly of relay H2, its normally closed contact Ill, line [I .09 to the intermediatecontact of a make-before- 7o break assembly of relay I08, its normally closed contact or, line 10a to the intermediate contact of a make-before-break assembly of relay I05, its

normally closed contact I 04, line I 03, to theintermediate contact of a make-before-break assembly of relay I82, its normally closed contact IIII, line 99 to the intermediate contact of a make-beforebreak assembly of relay 61, its normally closed contact 98 to locking negative supply line 88 already described. I

Z The outlying station I Iw ill next send a blank signal code combination, since as has been presumed there is to be selected the space-blank relay 61. When this signal is transmitted, blank contact 54 is closed byits associated pull bar H8 and negativepotential is extended over the blank conductor 85, through contact tongue II9 (now provided over conductor 88 through the contact tongue 98 thus providing a holding circuit for space-blank relay 61.

' With conditioning relay 62 and 63 thus energized and with space-blank relay 61 selected for operation, the transmitting station II will next 'send' a second carriage return signal which will be effectiveto cause the operation of thethird conditioning relay 6I' overthe following circuit,

traceable from negative conductor 13, through platen shift contact pair 58, through the'uni- 'versal bar opera-ted contact pair 51, through the carriage return contact pair 55 (now closed), over conductor 12, through contacttongue H of conditioning relay 63 (nowattracted), over'theconduotors I25 and I16, through the winding of relay BI, over conductors 66 and 66 to the positive con- 'ductor65. r,

, Relay 6Iis energized andattracts its tongue 12'! establishing a locking circuit for itself'as follows: From positive conductor 65, over conductors '66" and 66 through the winding of relay 6|,

through contact tongue I21, over conductor 81, through contact tongue 86, of conditioning relay 63 (now energized), to the negative conductor 13. Furthermore, the operation of the conditioningrelay 61 causes the attraction of its contact tongue BI and breaks the negative supply circuit extending to the letters shift, space, and blank contacts. The closing of contact tongue I21 by the conditioning relay 6| further extends negative potential over the conductor I28 for the shunt relays 34, 35, 36, and 31 as follows: from negative conductor 13, through contact tongue 4 86 of conditioning relay 63, over the conductor "81, throughcontact tongue I21 of conditioning relay 6| and over conductor I26 to the conductor I 2 8. during message transmission.

It will now be described how the spaceblank Relays BI, 62, and 63are thus energized functions sothat the accompanying messagejmay be transmitted over the transmitting lines 48 and I by their associated transmitters 44 and 46.

- Each'of the selecting relays, Fig. 3, is provided with four contact tongues I34, I35, I36, and I31 which cooperate with the reperforator shuntin relay 61' which has been selectedfor operation,

relays 34,35, 36, and 31 to remove the shunt circuits therefrom; (Whether or not contactoperat ing tongues I34 tel 31 will be effective toselect shunt relays-34 to 31 for operation depends on whether or not the contact tongues are connected by strap conductors I38 to acommon bus bar I39 which in'turn is connected to either conductor I4I, I50, or I5I. lead to the conductor I28 which was conditioned to carry negative potential upon operation of conditioning relays SI and 63 as described.

, From an inspection of Fig. 3, it may be seen that contact tongues I31 and I35 of relay 61 are provided with strap conductors I38 which extend to the bus bar I39, whereas no strap conductors are found in the case of the contact tongues I34 and I36. Thuscontact tongue I31of space-blank relay 61 will function to energize reperforator shunt relay-31 to remove the shunt circuit from the reperforator 25 and to thereby permit its operation as follows: from negative conditioned conductor I28, over conductor I4I, the bus bar I39, over the strapiconductor I38, through contact tongue I31 (now attracted), over conductor I42, and I43, through the winding of relay 31 to the positiveconductor 65.

A similar circuit for theshunt relay 35 is made through the contact tongue I35 of space-blank relay61 asfollows: from negative branch conductor I28, over conductor I4I, over thebus bar I39, through the strap conductor I38, contact tongue I35 of relay 61, conductors I 45, I46, and

I41, through the winding of shunt relay 35, over conductors I48 and I44 to the positive conductor 65. Thus the reperforator shunt relays 35 and 31 are operated to attract, their associated contact tongues 38 to remove the shunt circuits from The circuit embodied in the present system is provided primarily to transmit messages which are less than one line in length, to the reperforators and, consequently, the circuit is so designedtthat the operation of the line feed contact 56 will cause the de-energization of the conditioning relay BI, 62, and I53 after termination of each message and return the circuit to normal. However, it is understood that messages more than one line in length may-be transmitted by repeating the preassigned signal code combination for each new line of transmission. Thus, upon receipt of the line feed signal at the termination of a message which is primarily sent to efiect the performance of a line' feed operation on a page printer, "contact 56 is opened breaking the locking circuit extending overconductor' 16 to relays 62and'63.

The de-energization of relay 63 causes contact tongue 86*to recede'and, consequently, the locking circuit extending over conductor 81 to conditioning relay 6| is broken. The de-energization of conditioning relay 63 also breaks the locking circuit extending over conductor 88 for the selecting relays 61, 89, 95,etc., permitting the de-energization of the particular one of them which happened'to have been selected and further causes the removalofnegative potential from Conductors I4I, I58, and I5I the circuit '1 28 which is provided for the operation of the shunt reperforator relays as described.

In this manner any combination of the total available reperforators22 to 25 may be rendered effective to prepare control forms for operating the retransmitters 43 to 46 and thereby cause the transmission of the messages over lines 41 to 5I correspondingly. By using'nine shunt selecting relays 61, 89, 95, etc, there may be attained nine possible selective conditions. Where a larger variety of conditions may be desired, the described practice may be enlarged and a correspondingly greater series of shunt selector relays utilized. Each message is terminated by sending a concluding end-of-message signal consisting of the line feed combination and thereafter the system is in readiness to respond to another message including another identification or address signal.

If the space-letters shift identification signal combination is transmitted by one of the broad cast station I I, I2, I3,,etc., the space relay .89 first becomes locked up upon receipt of the space signal as has already been described. When the letters shift signal is thereafter transmitted and tended from negative conductor 82, as described, over line 83, through contact tongue I54 of blank relay 95, over the conductor I55, through contact tongue I63, over the conductor I51, through the winding of space letters relay H5 and over the conductor I58 to the positive conductor 65. Operation of the space-letters shift relay I I5 to attract its tongue I I enables the make-beforebreak contact I I4 to open the locking circuit extending to the previously locked up relay 89 and at the same timeenables the locking up of the space-letters relay I I5, since with respect to relay H5, straps I38 are provided only for contact tongues I36 and I37. Accordingly, reperforator shunt relays 36 and 31 will be selected for operation permittingfsignals to be sent over the lines I and 49 to the exclusion of lines 41 and 48.

In this manner each one of the sh nt selecting relays 61, 89, 95, etc., may be individually conditioned under the supervision of one'or two of the identification signals made up of a combina- ,tion of the letters shift, space, or blank signal trated 0nthe accompanying drawings, it is to be understood, nevertheless, that numerous modifications and variations may be admitted without departing from the essential spirit or scope thereof. Accordingly, it is not intended'to be limited by the particular language employed in the foregoing detailed specification nor by the illustrations in the accompanying drawings except as indicated in the hereunto appended claims.

What is claimed is: 1. In a telegraph system, a'multiple contact controller responsive to code signals over an incoming line, a series of selector relays, means responsive to divers operations of said contact controller for selectively operating one of said selector relays, a group of retransmission circuits,

, 25 letters shift contact 52 closes, a circuit is exand a control apparatus associated with each of said selectorrelays for establishing communication between saidincoming line and different combinations of said retransmission circuits,

whereby upon the operation of one of said selector relays communication will be established with a predetermined combination of said retransmission circuits.

2. In a telegraph system, an apparatus responsive to code signals received over an incoming line for, correspondingly operating a series of contacts, a set of selector relays, means responsive to divers operations of said apparatus for selectively operating oneof said selector relays, a group of retransmission circuits, and a control apparatus associatedwith each one of said selector relays comprising a contact pair corresponding to each one of said retransmission circuits for establishing communication between said incoming line and any combination of said retransmission circuits, whereby upon'the operation of one of said selector relays communication will be established with a predetermined combination of said retransmission circuits.

3. In a telegraph system, a plurality of transmitting. stations serially connected, a selector mechanism responsive to function code signals transmitted by said transmitting stations, a plurality of selector relays each responsive to a predetermined combination of the function signals,

and a plurality of retransmission devices connected in predetermined combinations to each of said selector relays wherebywhen one of said selector relays is operated said predetermined retransmission devices-connected thereto will be operated.

4. In a telegraph system, a plurality of transmitting stations serially connected, a selector mechanism responsive to function code signals transmitted by said transmitting stations, a pluralityof selector relays each responsive to a predetermined combination of the function signals, a plurality of retransmission devices connected in predetermined combinations to each of said selector relays whereby when one of said selector relays is operated said predetermined retransmission devices connected thereto will be operated, and means for releasing operated ones of said selector relays in response to a concluding function signal transmitted by said transmitting stations.

5. In a telegraph system, a plurality of transmitting stations serially connected, a selector mechanism responsive to function code signals transmitted by said transmitting stations, conditioning means responsive to some of the function code signals, a plurality of selector relays each responsive to a predetermined combination ,of other of the function signals operating after the operation of said conditioning means, and a plurality of retransmission devices connected in predetermined. combinations to eachof said selector relays whereby when one of said selector relays is operated said predetermined retransmission devices connected thereto will be oper- -ated.

6. In a telegraph system, an incoming line, a plurality of outgoing lines, a plurality of transmitters serially connected over said incoming line for transmittingmessages each comprised of in-' itial function code signals, intelligence code signals and a concluding function code signal, a selector mechanism responsive to the function code signals, conditioning means responsive to some of the initial function .code signals, a plurality of selector relays each responsive to a 'predetermined combination of other of the initial function signals operating after the operation of said conditioning means, a plurality of retransmission devices each connected to one of said outgoing lines and connected in predetermined combinations to each of said selector relays whereby when one of said selector relays is operated said predetermined retransmission devices connected thereto will be connected to said incoming line to transmit the intelligence code signals over its said outgoing lines, and means responsive to the concluding function code signal for releasing operated ones of said selector relays thereby disconnecting said incoming line from communication with said selected outgoing lines.

WALTER J. ZENNER. 

